CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER D—WATER PROGRAMS (Parts 100–149) > PART 131—WATER QUALITY STANDARDS > SUBPART D—Federally Promulgated Water Quality Standards (§131.31 to §131.42) > 131.36—Toxics criteria for those states not complying with Clean Water Act section 303(c)(2)(B).

131.36—Toxics criteria for those states not complying with Clean Water Act section 303(c)(2)(B).

(a) Scope. This section is not a general promulgation of the section 304(a) criteria for priority toxic pollutants but is restricted to specific pollutants in specific States.
(b) (1) EPA's Section 304(a) criteria for Priority Toxic Pollutants.
A BFreshwater CSaltwater DHuman Health(10−6 risk for carcinogens)For consumption of:
(#) Compound CAS Number CriterionMaximumConc. d(µg/L)(B1) CriterionContinuousConc. d(µg/L)(B2) CriterionMaximumConc. d(µg/L)(C1) CriterionContinuous Conc. d(µg/L)(C2) Water &Organisms(µg/L)(D1) OrganismsOnly(µg/L)(D2)
1 Antimony 7440360 14 a 4300 a
2 Arsenic 7440382 360 m 190 m 69 m 36 m 0.018 abc 0.14 abc
3 Beryllium 7440417 n n
4 Cadmium 7440439 3.7 e 1.0 e 42 m 9.3 m n n
5aChromium (III) 16065831 550 e 180 e n n
bChromium (VI) 18540299 15 m 10 m 1100 m 50 m n n
6 Copper 7440508 17 e 11 e 2.4 m 2.4 m
7 Lead 7439921 65 e 2.5 e 210 m 8.1 m n n
8 Mercury 7439976 2.1 m 0.012 ip 1.8 m 0.025 ip 0.14 0.15
9 Nickel 7440020 1400 e 160 e 74 m 8.2 m 610 a 4600 a
10 Selenium 7782492 20 p 5 p 290 m 71 m n n
11 Silver 7440224 3.4 e 1.9 m
12 Thallium 7440280 1.7 a 6.3 a
13 Zinc 7440666 110 e 100 e 90 m 81 m
14 Cyanide 57125 22 5.2 1 1 700 a 220000 aj
15 Asbestos 1332214 7,000,000 fibers/L k
16 2,3,7,8-TCDD (Dioxin) 1746016 0.000000013 c 0.000000014 c
17 Acrolein 107028 320 780
18 Acrylonitrile 107131 0.059 ac 0.66 ac
19 Benzene 71432 1.2 ac 71 ac
20 Bromoform 75252 4.3 ac 360 ac
21 Carbon Tetrachloride 56235 0.25 ac 4.4 ac
22 Chlorobenzene 108907 680 a 21000 aj
23 Chlorodibromomethane 124481 0.41 ac 34 ac
24 Chloroethane 75003
25 2-Chloroethylvinyl Ether 110758
26 Chloroform 67663 5.7 ac 470 ac
27 Dichlorobromomethane 75274 0.27 ac 22 ac
28 1,1-Dichloroethane 75343
29 1,2-Dichloroethane 107062 0.38 ac 99 ac
30 1,1-Dichloroethylene 75354 0.057 ac 3.2 ac
31 1,2-Dichloropropane 78875
32 1,3-Dichloropropylene 542756 10 a 1700 a
33 Ethylbenzene 100414 3100 a 29000 a
34 Methyl Bromide 74839 48 a 4000 a
35 Methyl Chloride 74873 n n
36 Methylene Chloride 75092 4.7 ac 1600 ac
37 1,1,2,2-Tetrachloroethane 79345 0.17 ac 11 ac
38 Tetrachloroethylene 127184 0.8 c 8.85 c
39 Toluene 108883 6800 a 200000 a
40 1,2-Trans-Dichloroethylene 156605
Code of Federal Regulations 483
41 1,1,1-Trichloroethane 71556 n n
42 1,1,2-Trichloroethane 79005 0.60 ac 42 ac
43 Trichloroethylene 79016 2.7 c 81 c
44 Vinyl Chloride 75014 2 c 525 c
45 2-Chlorophenol 95578
46 2,4-Dichlorophenol 120832 93 a 790 aj
47 2,4-Dimethylphenol 105679
48 2-Methyl-4,6-Dinitrophenol 534521 13.4 765
49 2,4-Dinitrophenol 51285 70 a 14000 a
50 2-Nitrophenol 88755
51 4-Nitrophenol 100027
52 3-Methyl-4-Chlorophenol 59507
53 Pentachlorophenol 87865 20 f 13 f 13 7.9 0.28 ac 8.2 acj
54 Phenol 108952 21000 a 4600000 aj
55 2,4,6-Trichlorophenol 88062 2.1 ac 6.5 ac
56 Acenaphthene 83329
57 Acenaphthylene 208968
58 Anthracene 120127 9600 a 110000 a
59 Benzidine 92875 0.00012 ac 0.00054 ac
60 Benzo(a)Anthracene 56553 0.0028 c 0.031 c
61 Benzo(a)Pyrene 50328 0.0028 c 0.031 c
62 Benzo(b)Fluoranthene 205992 0.0028 c 0.031 c
63 Benzo(ghi)Perylene 191242
64 Benzo(k)Fluoranthene 207089 0.0028 c 0.031 c
65 Bis(2-Chloroethoxy)Methane 111911
66 Bis(2-Chloroethyl)Ether 111444 0.031 ac 1.4 ac
67 Bis(2-Chloroisopropyl)Ether 108601 1400 a 170000 a
68 Bis(2-Ethylhexyl)Phthalate 117817 1.8 ac 5.9 ac
69 4-Bromophenyl Phenyl Ether 101553
70 Butylbenzyl Phthalate 85687
71 2-Chloronaphthalene 91587
72 4-Chlorophenyl Phenyl Ether 7005723
73 Chrysene 218019 0.0028 c 0.031 c
74 Dibenzo(ah)Anthracene 53703 0.0028 c 0.031 c
75 1,2-Dichlorobenzene 95501 2700 a 17000 a
76 1,3-Dichlorobenzene 541731 400 2600
77 1,4-Dichlorobenzene 106467 400 2600
78 3,3′-Dichlorobenzidine 91941 0.04 ac 0.077 ac
79 Diethyl Phthalate 84662 23000 a 120000 a
80 Dimethyl Phthalate 131113 313000 2900000
81 Di-n-Butyl Phthalate 84742 2700 a 12000 a
82 2,4-Dinitrotoluene 121142 0.11 c 9.1 c
83 2,6-Dinitrotoluene 606202
84 Di-n-Octyl Phthalate 117840
85 1,2-Diphenylhydrazine 122667 0.040 ac 0.54 ac
86 Fluoranthene 206440 300 a 370 a
87 Fluorene 86737 1300 a 14000 a
88 Hexachlorobenzene 118741 0.00075 ac 0.00077 ac
89 Hexachlorobutadiene 87683 0.44 ac 50 ac
90 Hexachlorocyclopentadiene 77474 240 a 17000 aj
Code of Federal Regulations 484
91 Hexachloroethane 67721 1.9 ac 8.9 ac
92 Indeno(1,2,3-cd)Pyrene 193395 0.0028 c 0.031 c
93 Isophorone 78591 8.4 ac 600 ac
94 Naphthalene 91203
95 Nitrobenzene 98953 17 a 1900 aj
96 N-Nitrosodimethylamine 62759 0.00069 ac 8.1 ac
97 N-Nitrosodi-n-Propylamine 621647
98 N-Nitrosodiphenylamine 86306 5.0 ac 16 ac
99 Phenanthrene 85018
100 Pyrene 129000 960 a 11000 a
101 1,2,4-Trichlorobenzene 120821
102 Aldrin 309002 3 g 1.3 g 0.00013 ac 0.00014 ac
103 alpha-BHC 319846 0.0039 ac 0.013 ac
104 beta-BHC 319857 0.014 ac 0.046 ac
105 gamma-BHC 58899 2 g 0.08 g 0.16 g 0.019 c 0.063 c
106 delta-BHC 319868
107 Chlordane 57749 2.4 g 0.0043 g 0.09 g 0.004 g 0.00057 ac 0.00059 ac
108 4,4′-DDT 50293 1.1 g 0.001 g 0.13 g 0.001 g 0.00059 ac 0.00059 ac
109 4,4′-DDE 72559 0.00059 ac 0.00059 ac
110 4,4′-DDD 72548 0.00083 ac 0.00084 ac
111 Dieldrin 60571 2.5 g 0.0019 g 0.71 g 0.0019 g 0.00014 ac 0.00014 ac
112 alpha-Endosulfan 959988 0.22 g 0.056 g 0.034 g 0.0087 g 0.93 a 2.0 a
113 beta-Endosulfan 33213659 0.22 g 0.056 g 0.034 g 0.0087 g 0.93 a 2.0 a
114 Endosulfan Sulfate 1031078 0.93 a 2.0 a
115 Endrin 72208 0.18 g 0.0023 g 0.037 g 0.0023 g 0.76 a 0.81 aj
116 Endrin Aldehyde 7421934 0.76 a 0.81 aj
117 Heptachlor 76448 0.52 g 0.0038 g 0.053 g 0.0036 g 0.00021 ac 0.00021 ac
118 Heptachlor Epoxide 1024573 0.52 g 0.0038 g 0.053 g 0.0036 g 0.00010 ac 0.00011 ac
119 PCB-1242 53469219 0.014 g 0.03 g
120 PCB-1254 11097691 0.014 g 0.03 g
121 PCB-1221 11104282 0.014 g 0.03 g
122 PCB-1232 11141165 0.014 g 0.03 g
123 PCB-1248 12672296 0.014 g 0.03 g
124 PCB-1260 11096825 0.014 g 0.03 g
125aPCB-1016 12674112 0.014 g 0.03 g
125bPolychlorinated biphenyls(PCBs) 0.00017 q 0.00017 q
126 Toxaphene 8001352 0.73 0.0002 0.21 0.0002 0.00073 ac 0.00075 ac
Total Number of Criteria (h) = 24 29 23 27 85 84
Footnotes
a. Criteria revised to reflect current agency q1* or RfD, as contained in the Integrated Risk Information System (IRIS). The fish tissue bioconcentration factor (BCF) from the 1980 criteria documents was retained in all cases.
b. The criteria refers to the inorganic form only.
c. Criteria in the matrix based on carcinogenicity (10−6 risk). For a risk level of 10−5, move the decimal point in the matrix value one place to the right.
d. Criteria Maximum Concentration (CMC) = the highest concentration of a pollutant to which aquatic life can be exposed for a short period of time (1-hour average) without deleterious effects. Criteria Continuous Concentration (CCC) = the highest concentration of a pollutant to which aquatic life can be exposed for an extended period of time (4 days) without deleterious effects. µg/L = micrograms per liter.
e. Freshwater aquatic life criteria for these metals are expressed as a function of total hardness (mg/L as CaCO3), the pollutant's water effect ratio (WER) as defined in § 131.36(c) and multiplied by an appropriate dissolved conversion factor as defined in § 131.36(b)(2). For comparative purposes, the values displayed in this matrix are shown as dissolved metal and correspond to a total hardness of 100 mg/L and a water effect ratio of 1.0.
f. Freshwater aquatic life criteria for pentachlorophenol are expressed as a function of pH, and are calculated as follows. Values displayed above in the matrix correspond to a pH of 7.8.
CMC = exp(1.005(pH)−4.830)
CCC = exp(1.005(pH)−5.290)
g. Aquatic life criteria for these compounds were issued in 1980 utilizing the 1980 Guidelines for criteria development. The acute values shown are final acute values (FAV) which by the 1980 Guidelines are instantaneous values as contrasted with a CMC which is a one-hour average.
h. These totals simply sum the criteria in each column. For aquatic life, there are 31 priority toxic pollutants with some type of freshwater or saltwater, acute or chronic criteria. For human health, there are 85 priority toxic pollutants with either “water fish” or “fish only” criteria. Note that these totals count chromium as one pollutant even though EPA has developed criteria based on two valence states. In the matrix, EPA has assigned numbers 5a and 5b to the criteria for chromium to reflect the fact that the list of 126 priority toxic pollutants includes only a single listing for chromium.
i. If the CCC for total mercury exceeds 0.012 µg/l more than once in a 3-year period in the ambient water, the edible portion of aquatic species of concern must be analyzed to determine whether the concentration of methyl mercury exceeds the FDA action level (1.0 mg/kg). If the FDA action level is exceeded, the State must notify the appropriate EPA Regional Administrator, initiate a revision of its mercury criterion in its water quality standards so as to protect designated uses, and take other appropriate action such as issuance of a fish consumption advisory for the affected area.
j. No criteria for protection of human health from consumption of aquatic organisms (excluding water) was presented in the 1980 criteria document or in the 1986 Quality Criteria for Water. Nevertheless, sufficient information was presented in the 1980 document to allow a calculation of a criterion, even though the results of such a calculation were not shown in the document.
k. The criterion for asbestos is the MCL (56 FR 3526, January 30, 1991).
l. [Reserved: This letter not used as a footnote.]
m. Criteria for these metals are expressed as a function of the water effect ratio, WER, as defined in 40 CFR 131.36(c).
CMC = column B1 or C1 value × WER
CCC = column B2 or C2 value × WER
n. EPA is not promulgating human health criteria for this contaminant. However, permit authorities should address this contaminant in NPDES permit actions using the State's existing narrative criteria for toxics.
o. [Reserved: This letter not used as a footnote.]
p. Criterion expressed as total recoverable.
q. This criterion applies to total PCBs (e.g., the sum of all congener or isomer or homolog or Aroclor analyses).
General Notes
1. This chart lists all of EPA's priority toxic pollutants whether or not criteria recommendations are available. Blank spaces indicate the absence of criteria recommendations. Because of variations in chemical nomenclature systems, this listing of toxic pollutants does not duplicate the listing in Appendix A of 40 CFR Part 423. EPA has added the Chemical Abstracts Service (CAS) registry numbers, which provide a unique identification for each chemical.
2. The following chemicals have organoleptic based criteria recommendations that are not included on this chart (for reasons which are discussed in the preamble): copper, zinc, chlorobenzene, 2-chlorophenol, 2,4-dichlorophenol, acenaphthene, 2,4-dimethylphenol, 3-methyl-4-chlorophenol, hexachlorocyclopentadiene, pentachlorophenol, phenol.
3. For purposes of this rulemaking, freshwater criteria and saltwater criteria apply as specified in 40 CFR 131.36(c).
(2) Factors for Calculating Hardness-Dependent, Freshwater Metals Criteria
CMC=WER exp { mA[ln(hardness)] bA} × Acute Conversion Factor
CCC=WER exp { mC[ln(hardness)] bC} × Chronic Conversion Factor
Final CMC and CCC values should be rounded to two significant figures.
(c) Applicability. (1) The criteria in paragraph (b) of this section apply to the States' designated uses cited in paragraph (d) of this section and supersede any criteria adopted by the State, except when State regulations contain criteria which are more stringent for a particular use in which case the State's criteria will continue to apply.
(2) The criteria established in this section are subject to the State's general rules of applicability in the same way and to the same extent as are the other numeric toxics criteria when applied to the same use classifications including mixing zones, and low flow values below which numeric standards can be exceeded in flowing fresh waters.
(i) For all waters with mixing zone regulations or implementation procedures, the criteria apply at the appropriate locations within or at the boundary of the mixing zones; otherwise the criteria apply throughout the waterbody including at the end of any discharge pipe, canal or other discharge point.
(ii) A State shall not use a low flow value below which numeric standards can be exceeded that is less stringent than the following for waters suitable for the establishment of low flow return frequencies (i.e., streams and rivers):
Where:
CMC—criteria maximum concentration—the water quality criteria to protect against acute effects in aquatic life and is the highest instream concentration of a priority toxic pollutant consisting of a one-hour average not to be exceeded more than once every three years on the average;
CCC—criteria continuous concentration—the water quality criteria to protect against chronic effects in aquatic life is the highest instream concentration of a priority toxic pollutant consisting of a 4-day average not to be exceeded more than once every three years on the average;
1 Q 10 is the lowest one day flow with an average recurrence frequency of once in 10 years determined hydrologically;
1 B 3 is biologically based and indicates an allowable exceedence of once every 3 years. It is determined by EPA's computerized method (DFLOW model);
7 Q 10 is the lowest average 7 consecutive day low flow with an average recurrence frequency of once in 10 years determined hydrologically;
4 B 3 is biologically based and indicates an allowable exceedence for 4 consecutive days once every 3 years. It is determined by EPA's computerized method (DFLOW model);
30 Q 5 is the lowest average 30 consecutive day low flow with an average recurrence frequency of once in 5 years determined hydrologically; and the harmonic mean flow is a long term mean flow value calculated by dividing the number of daily flows analyzed by the sum of the reciprocals of those daily flows.
(iii) If a State does not have such a low flow value for numeric standards compliance, then none shall apply and the criteria included in paragraph (d) of this section herein apply at all flows.
(3) The aquatic life criteria in the matrix in paragraph (b) of this section apply as follows:
(i) For waters in which the salinity is equal to or less than 1 part per thousand 95% or more of the time, the applicable criteria are the freshwater criteria in Column B;
(ii) For waters in which the salinity is equal to or greater than 10 parts per thousand 95% or more of the time, the applicable criteria are the saltwater criteria in Column C; and
(iii) For waters in which the salinity is between 1 and 10 parts per thousand as defined in paragraphs (c)(3) (i) and (ii) of this section, the applicable criteria are the more stringent of the freshwater or saltwater criteria. However, the Regional Administrator may approve the use of the alternative freshwater or saltwater criteria if scientifically defensible information and data demonstrate that on a site-specific basis the biology of the waterbody is dominated by freshwater aquatic life and that freshwater criteria are more appropriate; or conversely, the biology of the waterbody is dominated by saltwater aquatic life and that saltwater criteria are more appropriate.
(4) Application of metals criteria. (i) For purposes of calculating freshwater aquatic life criteria for metals from the equations in paragraph (b)(2) of this section, the minimum hardness allowed for use in those equations shall not be less than 25 mg/l, as calcium carbonate, even if the actual ambient hardness is less than 25 mg/l as calcium carbonate. The maximum hardness value for use in those equations shall not exceed 400 mg/l as calcium carbonate, even if the actual ambient hardness is greater than 400 mg/l as calcium carbonate. The same provisions apply for calculating the metals criteria for the comparisons provided for in paragraph (c)(3)(iii) of this section.
(ii) The hardness values used shall be consistent with the design discharge conditions established in paragraph (c)(2) of this section for flows and mixing zones.
(iii) Except where otherwise noted, the criteria for metals (compounds #2, #4-# 11, and #13, in paragraph (b) of this section) are expressed as dissolved metal. For purposes of calculating aquatic life criteria for metals from the equations in footnote m. in the criteria matrix in paragraph (b)(1) of this section and the equations in paragraphs (b)(2) of this section, the water-effect ratio is computed as a specific pollutant's acute or chronic toxicity values measured in water from the site covered by the standard, divided by the respective acute or chronic toxicity value in laboratory dilution water.
(d) Criteria for Specific Jurisdictions— (1) Rhode Island, EPA Region 1. All waters assigned to the following use classifications in the Water Quality Regulations for Water Pollution Control adopted under Chapters 46-12, 42-17.1, and 42-35 of the General Laws of Rhode Island are subject to the criteria in paragraph (d)(1)(ii) of this section, without exception:
6.21 Freshwater 6.22 Saltwater:
Class A Class SA
Class B Class SB
Class C Class SC
(ii) The following criteria from the matrix in paragraph (b)(1) of this section apply to the use classifications identified in paragraph (d)(1)(i) of this section:
Use classification Applicable criteria
Class AClass B waters where water supply use is designated These classifications are assigned the criteria in Column D1—#2, 68
Class B waters where water supply use is not designated Class C; Class SA; Class SB; Class SC Each of these classifications is assigned the criteria in: Column D2—#2, 68
(iii) The human health criteria shall be applied at the 10−5 risk level, consistent with the State policy. To determine appropriate value for carcinogens, see footnote c in the criteria matrix in paragraph (b)(1) of this section.
(2) Vermont, EPA Region 1. (i) All waters assigned to the following use classifications in the Vermont Water Quality Standards adopted under the authority of the Vermont Water Pollution Control Act (10 V.S.A., Chapter 47) are subject to the criteria in paragraph (d)(2)(ii) of this section, without exception:
Class A
Class B
Class C
(ii) The following criteria from the matrix in paragraph (b)(1) of this section apply to the use classifications identified in paragraph (d)(2)(i) of this section:
Use classification Applicable criteria
1. Classes A1, A2, B1, B2, B3 These classification are assigned the criterion in:Column B2—#105.
(iii) The human health criteria shall be applied at the State-proposed 10−6 risk level.
(3) New Jersey, EPA Region 2. (i) All waters assigned to the following use classifications in the New Jersey Administrative Code (N.J.A.C.) 7:9-4.1 et seq., Surface Water Quality Standards, are subject to the criteria in paragraph (d)(3)(ii) of this section, without exception.
N.J.A.C. 7:9-4.12(b): Class PL
N.J.A.C. 7:9-4.12(c): Class FW2
N.J.A.C. 7:9-4.12(d): Class SE1
N.J.A.C. 7:9-4.12(e): Class SE2
N.J.A.C. 7:9-4.12(f): Class SE3
N.J.A.C. 7:9-4.12(g): Class SC
N.J.A.C. 7:9-4.13(a): Delaware River Zones 1C, 1D, and 1E
N.J.A.C. 7:9-4.13(b): Delaware River Zone 2
N.J.A.C. 7:9-4.13(c): Delaware River Zone 3
N.J.A.C. 7:9-4.13(d): Delaware River Zone 4
N.J.A.C. 7:9-4.13(e): Delaware River Zone 5
N.J.A.C. 7:9-4.13(f): Delaware River Zone 6
(ii) The follo